Merge "Refine surrounding text logic and test case readability." (4b41675b) · Commits · e / os / android_frameworks_base

core/java/android/view/inputmethod/EditorInfo.java

+43 −33

Original line number	Diff line number	Diff line
		@@ -33,11 +33,11 @@ import android.util.Printer;
		import android.view.View;

		import com.android.internal.annotations.VisibleForTesting;
		import com.android.internal.util.Preconditions;

		import java.lang.annotation.Retention;
		import java.lang.annotation.RetentionPolicy;
		import java.util.Arrays;
		import java.util.Objects;

		/**
		* An EditorInfo describes several attributes of a text editing object
		@@ -558,7 +558,7 @@ public class EditorInfo implements InputType, Parcelable {
		* editor wants to trim out the first 10 chars, subTextStart should be 10.
		*/
		public void setInitialSurroundingSubText(@NonNull CharSequence subText, int subTextStart) {
		Preconditions.checkNotNull(subText);
		Objects.requireNonNull(subText);

		// Swap selection start and end if necessary.
		final int subTextSelStart = initialSelStart > initialSelEnd
		@@ -585,25 +585,35 @@ public class EditorInfo implements InputType, Parcelable {
		return;
		}

		// The input text is too long. Let's try to trim it reasonably. Fundamental rules are:
		// 1. Text before the cursor is the most important information to IMEs.
		// 2. Text after the cursor is the second important information to IMEs.
		// 3. Selected text is the least important information but it shall NEVER be truncated.
		// When it is too long, just drop it.
		//
		// Source: <TextBeforeCursor><Selection><TextAfterCursor>
		// Possible results:
		// 1. <(maybeTrimmedAtHead)TextBeforeCursor><Selection><TextAfterCursor(maybeTrimmedAtTail)>
		// 2. <(maybeTrimmedAtHead)TextBeforeCursor><TextAfterCursor(maybeTrimmedAtTail)>
		//
		final int sourceSelLength = subTextSelEnd - subTextSelStart;
		trimLongSurroundingText(subText, subTextSelStart, subTextSelEnd);
		}

		/**
		* Trims the initial surrounding text when it is over sized. Fundamental trimming rules are:
		* - The text before the cursor is the most important information to IMEs.
		* - The text after the cursor is the second important information to IMEs.
		* - The selected text is the least important information but it shall NEVER be truncated. When
		* it is too long, just drop it.
		*<p><pre>
		* For example, the subText can be viewed as
		* TextBeforeCursor + Selection + TextAfterCursor
		* The result could be
		* 1. (maybeTrimmedAtHead)TextBeforeCursor + Selection + TextAfterCursor(maybeTrimmedAtTail)
		* 2. (maybeTrimmedAtHead)TextBeforeCursor + TextAfterCursor(maybeTrimmedAtTail)</pre>
		*
		* @param subText The long text that needs to be trimmed.
		* @param selStart The text offset of the start of the selection.
		* @param selEnd The text offset of the end of the selection
		*/
		private void trimLongSurroundingText(CharSequence subText, int selStart, int selEnd) {
		final int sourceSelLength = selEnd - selStart;
		// When the selected text is too long, drop it.
		final int newSelLength = (sourceSelLength > MAX_INITIAL_SELECTION_LENGTH)
		? 0 : sourceSelLength;

		// Distribute rest of length quota to TextBeforeCursor and TextAfterCursor in 4:1 ratio.
		final int subTextBeforeCursorLength = subTextSelStart;
		final int subTextAfterCursorLength = subTextLength - subTextSelEnd;
		final int subTextBeforeCursorLength = selStart;
		final int subTextAfterCursorLength = subText.length() - selEnd;
		final int maxLengthMinusSelection = MEMORY_EFFICIENT_TEXT_LENGTH - newSelLength;
		final int possibleMaxBeforeCursorLength =
		Math.min(subTextBeforeCursorLength, (int) (0.8 * maxLengthMinusSelection));
		@@ -617,24 +627,23 @@ public class EditorInfo implements InputType, Parcelable {

		// We don't want to cut surrogate pairs in the middle. Exam that at the new head and tail.
		if (isCutOnSurrogate(subText,
		subTextSelStart - newBeforeCursorLength, TrimPolicy.HEAD)) {
		selStart - newBeforeCursorLength, TrimPolicy.HEAD)) {
		newBeforeCursorHead = newBeforeCursorHead + 1;
		newBeforeCursorLength = newBeforeCursorLength - 1;
		}
		if (isCutOnSurrogate(subText,
		subTextSelEnd + newAfterCursorLength - 1, TrimPolicy.TAIL)) {
		selEnd + newAfterCursorLength - 1, TrimPolicy.TAIL)) {
		newAfterCursorLength = newAfterCursorLength - 1;
		}

		// Now we know where to trim, compose the initialSurroundingText.
		final int newTextLength = newBeforeCursorLength + newSelLength + newAfterCursorLength;
		CharSequence newInitialSurroundingText;
		final CharSequence newInitialSurroundingText;
		if (newSelLength != sourceSelLength) {
		final CharSequence beforeCursor = subText.subSequence(newBeforeCursorHead,
		newBeforeCursorHead + newBeforeCursorLength);

		final CharSequence afterCursor = subText.subSequence(subTextSelEnd,
		subTextSelEnd + newAfterCursorLength);
		final CharSequence afterCursor = subText.subSequence(selEnd,
		selEnd + newAfterCursorLength);

		newInitialSurroundingText = TextUtils.concat(beforeCursor, afterCursor);
		} else {
		@@ -651,15 +660,16 @@ public class EditorInfo implements InputType, Parcelable {
		}

		/**
		* Get <var>n</var> characters of text before the current cursor position. May be {@code null}
		* when the protocol is not supported.
		* Get <var>length</var> characters of text before the current cursor position. May be
		* {@code null} when the protocol is not supported.
		*
		* @param length The expected length of the text.
		* @param flags Supplies additional options controlling how the text is returned. May be
		* either 0 or {@link InputConnection#GET_TEXT_WITH_STYLES}.
		* @return the text before the cursor position; the length of the returned text might be less
		* than <var>n</var>. When there is no text before the cursor, an empty string will be returned.
		* It could also be {@code null} when the editor or system could not support this protocol.
		* than <var>length</var>. When there is no text before the cursor, an empty string will be
		* returned. It could also be {@code null} when the editor or system could not support this
		* protocol.
		*/
		@Nullable
		public CharSequence getInitialTextBeforeCursor(int length, int flags) {
		@@ -667,8 +677,8 @@ public class EditorInfo implements InputType, Parcelable {
		}

		/**
		* Gets the selected text, if any. May be {@code null} when no text is selected or the selected
		* text is way too long.
		* Gets the selected text, if any. May be {@code null} when the protocol is not supported or the
		* selected text is way too long.
		*
		* @param flags Supplies additional options controlling how the text is returned. May be
		* either 0 or {@link InputConnection#GET_TEXT_WITH_STYLES}.
		@@ -693,15 +703,16 @@ public class EditorInfo implements InputType, Parcelable {
		}

		/**
		* Get <var>n</var> characters of text after the current cursor position. May be {@code null}
		* when the protocol is not supported.
		* Get <var>length</var> characters of text after the current cursor position. May be
		* {@code null} when the protocol is not supported.
		*
		* @param length The expected length of the text.
		* @param flags Supplies additional options controlling how the text is returned. May be
		* either 0 or {@link InputConnection#GET_TEXT_WITH_STYLES}.
		* @return the text after the cursor position; the length of the returned text might be less
		* than <var>n</var>. When there is no text after the cursor, an empty string will be returned.
		* It could also be {@code null} when the editor or system could not support this protocol.
		* than <var>length</var>. When there is no text after the cursor, an empty string will be
		* returned. It could also be {@code null} when the editor or system could not support this
		* protocol.
		*/
		@Nullable
		public CharSequence getInitialTextAfterCursor(int length, int flags) {
		@@ -863,7 +874,6 @@ public class EditorInfo implements InputType, Parcelable {
		return 0;
		}

		// TODO(b/148035211): Unit tests for this class
		static final class InitialSurroundingText implements Parcelable {
		@Nullable final CharSequence mSurroundingText;
		final int mSelectionHead;

core/tests/coretests/src/android/view/inputmethod/EditorInfoTest.java

+105 −95

Original line number	Diff line number	Diff line
		@@ -20,11 +20,11 @@ import static org.junit.Assert.assertEquals;
		import static org.junit.Assert.assertNull;
		import static org.junit.Assert.assertTrue;
		import static org.junit.Assert.fail;
		import static org.mockito.ArgumentMatchers.anyInt;

		import android.annotation.Nullable;
		import android.os.Parcel;
		import android.os.UserHandle;
		import android.text.Spannable;
		import android.text.SpannableStringBuilder;
		import android.text.TextUtils;

		@@ -41,6 +41,7 @@ import org.junit.runner.RunWith;
		@RunWith(AndroidJUnit4.class)
		public class EditorInfoTest {
		private static final int TEST_USER_ID = 42;
		private static final int LONG_EXP_TEXT_LENGTH = EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH * 2;

		/**
		* Makes sure that {@code null} {@link EditorInfo#targetInputMethodUser} can be copied via
		@@ -79,8 +80,8 @@ public class EditorInfoTest {
		}

		@Test
		public void testNullTextInputComposeInitialSurroundingText() {
		final Spannable testText = null;
		public void setInitialText_nullInputText_throwsException() {
		final CharSequence testText = null;
		final EditorInfo editorInfo = new EditorInfo();

		try {
		@@ -92,56 +93,75 @@ public class EditorInfoTest {
		}

		@Test
		public void testNonNullTextInputComposeInitialSurroundingText() {
		final Spannable testText = createTestText(/* prependLength= */ 0,
		EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);
		final EditorInfo editorInfo = new EditorInfo();
		public void setInitialText_cursorAtHead_dividesByCursorPosition() {
		final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);

		// Cursor at position 0.
		int selectionLength = 0;
		final EditorInfo editorInfo = new EditorInfo();
		final int selectionLength = 0;
		editorInfo.initialSelStart = 0;
		editorInfo.initialSelEnd = editorInfo.initialSelStart + selectionLength;
		int expectedTextBeforeCursorLength = 0;
		int expectedTextAfterCursorLength = testText.length();
		final int expectedTextBeforeCursorLength = 0;
		final int expectedTextAfterCursorLength = testText.length();

		editorInfo.setInitialSurroundingText(testText);

		assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,
		expectedTextAfterCursorLength);
		}

		// Cursor at the end.
		@Test
		public void setInitialText_cursorAtTail_dividesByCursorPosition() {
		final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);
		final EditorInfo editorInfo = new EditorInfo();
		final int selectionLength = 0;
		editorInfo.initialSelStart = testText.length() - selectionLength;
		editorInfo.initialSelEnd = testText.length();
		expectedTextBeforeCursorLength = testText.length();
		expectedTextAfterCursorLength = 0;
		final int expectedTextBeforeCursorLength = testText.length();
		final int expectedTextAfterCursorLength = 0;

		editorInfo.setInitialSurroundingText(testText);

		assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,
		expectedTextAfterCursorLength);
		}

		// Cursor at the middle.
		selectionLength = 2;
		@Test
		public void setInitialText_cursorAtMiddle_dividesByCursorPosition() {
		final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);
		final EditorInfo editorInfo = new EditorInfo();
		final int selectionLength = 2;
		editorInfo.initialSelStart = testText.length() / 2;
		editorInfo.initialSelEnd = editorInfo.initialSelStart + selectionLength;
		expectedTextBeforeCursorLength = editorInfo.initialSelStart;
		expectedTextAfterCursorLength = testText.length() - editorInfo.initialSelEnd;
		final int expectedTextBeforeCursorLength = editorInfo.initialSelStart;
		final int expectedTextAfterCursorLength = testText.length() - editorInfo.initialSelEnd;

		editorInfo.setInitialSurroundingText(testText);

		assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,
		expectedTextAfterCursorLength);
		}

		// Accidentally swap selection start and end.
		@Test
		public void setInitialText_incorrectCursorOrder_correctsThenDivide() {
		final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);
		final EditorInfo editorInfo = new EditorInfo();
		final int selectionLength = 2;
		editorInfo.initialSelEnd = testText.length() / 2;
		editorInfo.initialSelStart = editorInfo.initialSelEnd + selectionLength;
		final int expectedTextBeforeCursorLength = testText.length() / 2;
		final int expectedTextAfterCursorLength = testText.length() - testText.length() / 2
		- selectionLength;

		editorInfo.setInitialSurroundingText(testText);

		assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,
		expectedTextAfterCursorLength);
		}

		// Invalid cursor position.
		@Test
		public void setInitialText_invalidCursorPosition_returnsNull() {
		final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);
		final EditorInfo editorInfo = new EditorInfo();
		editorInfo.initialSelStart = -1;

		editorInfo.setInitialSurroundingText(testText);
		@@ -153,64 +173,33 @@ public class EditorInfoTest {
		}

		@Test
		public void testTooLongTextInputComposeInitialSurroundingText() {
		final Spannable testText = createTestText(/* prependLength= */ 0,
		EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH + 2);
		public void setOverSizeInitialText_cursorAtMiddle_dividesProportionately() {
		final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH + 2);
		final EditorInfo editorInfo = new EditorInfo();

		// Cursor at position 0.
		int selectionLength = 0;
		editorInfo.initialSelStart = 0;
		editorInfo.initialSelEnd = 0 + selectionLength;
		int expectedTextBeforeCursorLength = 0;
		int expectedTextAfterCursorLength = editorInfo.MEMORY_EFFICIENT_TEXT_LENGTH;

		editorInfo.setInitialSurroundingText(testText);

		assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,
		expectedTextAfterCursorLength);

		// Cursor at the end.
		editorInfo.initialSelStart = testText.length() - selectionLength;
		editorInfo.initialSelEnd = testText.length();
		expectedTextBeforeCursorLength = editorInfo.MEMORY_EFFICIENT_TEXT_LENGTH;
		expectedTextAfterCursorLength = 0;

		editorInfo.setInitialSurroundingText(testText);

		assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,
		expectedTextAfterCursorLength);

		// Cursor at the middle.
		selectionLength = 2;
		final int selectionLength = 2;
		editorInfo.initialSelStart = testText.length() / 2;
		editorInfo.initialSelEnd = editorInfo.initialSelStart + selectionLength;
		expectedTextBeforeCursorLength = Math.min(editorInfo.initialSelStart,
		final int expectedTextBeforeCursorLength = Math.min(editorInfo.initialSelStart,
		(int) (0.8 * (EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH - selectionLength)));
		expectedTextAfterCursorLength = EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH
		final int expectedTextAfterCursorLength = EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH
		- expectedTextBeforeCursorLength - selectionLength;

		editorInfo.setInitialSurroundingText(testText);

		assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,
		expectedTextAfterCursorLength);
		}

		// Accidentally swap selection start and end.
		editorInfo.initialSelEnd = testText.length() / 2;
		editorInfo.initialSelStart = editorInfo.initialSelEnd + selectionLength;

		editorInfo.setInitialSurroundingText(testText);

		assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,
		expectedTextAfterCursorLength);

		// Selection too long, selected text should be dropped.
		selectionLength = EditorInfo.MAX_INITIAL_SELECTION_LENGTH + 1;
		@Test
		public void setOverSizeInitialText_overSizeSelection_dropsSelection() {
		final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH + 2);
		final EditorInfo editorInfo = new EditorInfo();
		final int selectionLength = EditorInfo.MAX_INITIAL_SELECTION_LENGTH + 1;
		editorInfo.initialSelStart = testText.length() / 2;
		editorInfo.initialSelEnd = editorInfo.initialSelStart + selectionLength;
		expectedTextBeforeCursorLength = Math.min(editorInfo.initialSelStart,
		final int expectedTextBeforeCursorLength = Math.min(editorInfo.initialSelStart,
		(int) (0.8 * EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH));
		expectedTextAfterCursorLength = testText.length() - editorInfo.initialSelEnd;
		final int expectedTextAfterCursorLength = testText.length() - editorInfo.initialSelEnd;

		editorInfo.setInitialSurroundingText(testText);

		@@ -219,34 +208,59 @@ public class EditorInfoTest {
		}

		@Test
		public void testTooLongSubTextInputComposeInitialSurroundingText() {
		final int prependLength = 5;
		final int subTextLength = EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH;
		final Spannable fullText = createTestText(prependLength, subTextLength);
		public void setInitialSubText_trimmedSubText_dividesByOriginalCursorPosition() {
		final String prefixString = "prefix";
		final CharSequence subText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);
		final CharSequence originalText = TextUtils.concat(prefixString, subText);
		final EditorInfo editorInfo = new EditorInfo();
		// Cursor at the middle.
		final int selectionLength = 2;
		editorInfo.initialSelStart = fullText.length() / 2;
		editorInfo.initialSelEnd = editorInfo.initialSelStart + selectionLength;
		// #prependLength characters will be trimmed out.
		final Spannable expectedTextBeforeCursor = createExpectedText(/* startNumber= */0,
		editorInfo.initialSelStart - prependLength);
		final Spannable expectedSelectedText = createExpectedText(
		editorInfo.initialSelStart - prependLength, selectionLength);
		final Spannable expectedTextAfterCursor = createExpectedText(
		editorInfo.initialSelEnd - prependLength,
		fullText.length() - editorInfo.initialSelEnd);

		editorInfo.setInitialSurroundingSubText(fullText.subSequence(prependLength,
		fullText.length()), prependLength);
		final int selLength = 2;
		editorInfo.initialSelStart = originalText.length() / 2;
		editorInfo.initialSelEnd = editorInfo.initialSelStart + selLength;
		final CharSequence expectedTextBeforeCursor = createExpectedText(/* startNumber= */0,
		editorInfo.initialSelStart - prefixString.length());
		final CharSequence expectedSelectedText = createExpectedText(
		editorInfo.initialSelStart - prefixString.length(), selLength);
		final CharSequence expectedTextAfterCursor = createExpectedText(
		editorInfo.initialSelEnd - prefixString.length(),
		originalText.length() - editorInfo.initialSelEnd);

		editorInfo.setInitialSurroundingSubText(subText, prefixString.length());

		assertTrue(TextUtils.equals(expectedTextBeforeCursor,
		editorInfo.getInitialTextBeforeCursor(editorInfo.MEMORY_EFFICIENT_TEXT_LENGTH,
		InputConnection.GET_TEXT_WITH_STYLES)));
		editorInfo.getInitialTextBeforeCursor(LONG_EXP_TEXT_LENGTH, anyInt())));
		assertTrue(TextUtils.equals(expectedSelectedText,
		editorInfo.getInitialSelectedText(InputConnection.GET_TEXT_WITH_STYLES)));
		editorInfo.getInitialSelectedText(anyInt())));
		assertTrue(TextUtils.equals(expectedTextAfterCursor,
		editorInfo.getInitialTextAfterCursor(editorInfo.MEMORY_EFFICIENT_TEXT_LENGTH,
		editorInfo.getInitialTextAfterCursor(LONG_EXP_TEXT_LENGTH, anyInt())));
		}

		@Test
		public void initialSurroundingText_wrapIntoParcel_staysIntact() {
		// EditorInfo.InitialSurroundingText is not visible to test class. But all its key elements
		// must stay intact for its getter methods to return correct value and it will be wrapped
		// into its outer class for parcel transfer, therefore we can verify its parcel
		// wrapping/unwrapping logic through its outer class.
		final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);
		final EditorInfo sourceEditorInfo = new EditorInfo();
		final int selectionLength = 2;
		sourceEditorInfo.initialSelStart = testText.length() / 2;
		sourceEditorInfo.initialSelEnd = sourceEditorInfo.initialSelStart + selectionLength;
		sourceEditorInfo.setInitialSurroundingText(testText);

		final EditorInfo targetEditorInfo = cloneViaParcel(sourceEditorInfo);

		assertTrue(TextUtils.equals(
		sourceEditorInfo.getInitialTextBeforeCursor(LONG_EXP_TEXT_LENGTH,
		InputConnection.GET_TEXT_WITH_STYLES),
		targetEditorInfo.getInitialTextBeforeCursor(LONG_EXP_TEXT_LENGTH,
		InputConnection.GET_TEXT_WITH_STYLES)));
		assertTrue(TextUtils.equals(
		sourceEditorInfo.getInitialSelectedText(InputConnection.GET_TEXT_WITH_STYLES),
		targetEditorInfo.getInitialSelectedText(InputConnection.GET_TEXT_WITH_STYLES)));
		assertTrue(TextUtils.equals(
		sourceEditorInfo.getInitialTextAfterCursor(LONG_EXP_TEXT_LENGTH,
		InputConnection.GET_TEXT_WITH_STYLES),
		targetEditorInfo.getInitialTextAfterCursor(LONG_EXP_TEXT_LENGTH,
		InputConnection.GET_TEXT_WITH_STYLES)));
		}

		@@ -254,12 +268,12 @@ public class EditorInfoTest {
		@Nullable Integer expectBeforeCursorLength, @Nullable Integer expectSelectionLength,
		@Nullable Integer expectAfterCursorLength) {
		final CharSequence textBeforeCursor =
		editorInfo.getInitialTextBeforeCursor(editorInfo.MEMORY_EFFICIENT_TEXT_LENGTH,
		editorInfo.getInitialTextBeforeCursor(LONG_EXP_TEXT_LENGTH,
		InputConnection.GET_TEXT_WITH_STYLES);
		final CharSequence selectedText =
		editorInfo.getInitialSelectedText(InputConnection.GET_TEXT_WITH_STYLES);
		final CharSequence textAfterCursor =
		editorInfo.getInitialTextAfterCursor(editorInfo.MEMORY_EFFICIENT_TEXT_LENGTH,
		editorInfo.getInitialTextAfterCursor(LONG_EXP_TEXT_LENGTH,
		InputConnection.GET_TEXT_WITH_STYLES);

		if (expectBeforeCursorLength == null) {
		@@ -281,19 +295,15 @@ public class EditorInfoTest {
		}
		}

		private static Spannable createTestText(int prependLength, int surroundingLength) {
		private static CharSequence createTestText(int surroundingLength) {
		final SpannableStringBuilder builder = new SpannableStringBuilder();
		for (int i = 0; i < prependLength; i++) {
		builder.append("a");
		}

		for (int i = 0; i < surroundingLength; i++) {
		builder.append(Integer.toString(i % 10));
		}
		return builder;
		}

		private static Spannable createExpectedText(int startNumber, int length) {
		private static CharSequence createExpectedText(int startNumber, int length) {
		final SpannableStringBuilder builder = new SpannableStringBuilder();
		for (int i = startNumber; i < startNumber + length; i++) {
		builder.append(Integer.toString(i % 10));